Broderie perse is a fancy term for a type of sewing where you take pieces of fabric that already have designs on them, cut those designs out, and then sew them onto a bigger piece of fabric to make a cool new design. It's kind of like taking stickers and putting them on a piece of paper to make a picture.
The designs that you cut out can be from different types of fabrics, like flowers from a flowery fabric or animals from an animal print fabric. Once you have all the pieces cut out, you arrange them on a piece of fabric and sew them down. This can make really pretty patterns and designs that people can use to decorate things like clothing or quilts.
It's a bit like a puzzle because you have to pick the pieces you want and put them together in the right place to make the perfect design. It can take a lot of time and patience to cut out all the pieces and sew them down just right, but the result can be something really special and unique.